* Invalid file path when importing a single file
Adds a test that proves importing a single file sets the file name to
'.'
* Clean test a bit
* Expand test
* 💄 test
* One more test
* Appease the linter
* 💄
* Add missing fixture
* Set the right Filepath when processing single files
* Simpler fix suggested by @mholt
* Simplify tests
* Add clarifying comment
* Rename the test
